<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <script>
        // return 就是函数的一个执行结果，return语句执行后，函数终止执行
        function a(){
            return 1;
            console.log("a");
        }
        var b=a();
        console.log(b);
        </script>
</body>
</html>